In situ nano-Fe3O4/triisopropanolamine functionalized graphene oxide composites to enhance Pb2+ ions removal

In this work, a kind of magnetic graphene oxide composite material (TI/GO@Fe3O4) for Pb2+ removal was successfully synthesized through in situ growth method. Briefly, metal ions (Fe3+) were fixed on GO surface by oxygen-containing functional groups and acted as growth centers of Fe3O4. Furthermore, the surface of GO and Fe3O4 nanoparticles were strengthened by the triisopropanolamine and its oxidation products (TI), which can promote the removal of Pb2+ ions. The mass percentage of Fe3O4 particles in TI/GO@Fe3O4 was 54.31% by EDS datas. Average particle size of TI/GO@Fe3O4 is 19.03 nm. The adsorption experiments indicated that the adsorption capacity of TI/GO@Fe3O4 can reach 461.00 mg/g under optimized conditions (10 mg TI/GO@Fe3O4, 50 mL 500 mg/L Pb2+, pH 5.0, 293 K, 120 min). The XPS analysis results indicated that the TI/GO@Fe3O4 can adsorb the Pb2+ through the complexation between nitrogen and oxygen-containing functional groups and Pb2+ ions. Hence, the composite material is a superior material for the adsorption of Pb2+. Moreover, the synthesized adsorbent can be recycled by magnet quickly after adsorption.